Method for the manufacture of preferably multilayer cross-bottom bags of paper,plastic or the like



p 6. 1969 KARL-HEINZ HONSEL 3,

METHOD FOR THE MANUFACTURE OF PREFERABLY MULTILAYER CROSS-BOTTOM BAGS OF PAPER, PLASTIC OR THE LIKE Filed Aug. 9, 1966 5 Sheets-Sheet 1 12a Fig-7 12a 12 I 1 V A M mas Inventor: KAR wan/z 190M542 Sept. 16. 1969 KARL-HEINZ HONSEL 3,466,981

METHOD FOR THE MANUFACTURE OF PREFERABLY MULTILAYER CROSSBOTTQM BAGS OF PAPER, PLASTIC OR THE LIKE Filed Aug. 9, 1966 3 Sheets-Sheet 5 Inventor: K/Ml //f//VZ flat J22 United States Patent 3,466,981 METHOD FOR THE MANUFACTURE OF PREF- ERABLY MULTILAYER CROSS-BOTTOM BAGS OF PAPER, PLASTIC OR THE LIKE Karl-Heinz Honsel, Am Waldwinkel 16, Bielefeld, Germany Filed Aug. 9, 1966, Ser. No. 571,215 Claims priority, application Germany, Aug. 9, 1965, H 56,809 Int. Cl. 1331b 49/04, 1/14 11.5. C]. 93-35 2 Claims ABSTRACT OF THE DISCLOSURE Background of the invention This invention relates to the manufacture of crossbottom bags and is particularly concerned with the manufacture of cross-bottom bags of paper, plastic or the like that may have multilayer cross bottoms.

In the manufacture of cross-bottom bags of paper, plastic or the like, the practice requires more and more productive or efiicient machines, and beyond that it is required that in spite of the highest possible efliciency of the machines, cross-bottom bags are made with as little waste as possible, the cross-bottoms of which provide for very tight sealing.

These requirements for high efficiency and simultaneous attainment of a bag that is sealed against powdery materials are not met by the cross-bottom bag machines known heretofore. This is due on the one hand to the fact that the working operations required for forming the bottom follow a relatively complicated course. On the other hand, the cause of the shortcomings is that during the forming of the cross-bottom, which also involves a suitable application of glue, there frequently exists the danger that the individual folding or grooving tools or the like are soiled with the glue to be applied or already applied, and it is apparent that as a result an orderly and eflicient course of manufacture of individual cross-bottom bags is hampered.

Summary of the invention The invention is based on the problem of overcoming these difficulties. In order to solve this problem the invention begins with selecting a very particular cross-bottom bag that is known per se from a multitude of known cross-bottom bags, and to arrange the manufacturing procedure in the production of the chosen cross-bottom bag in such a manner that the course of operation in the forming of the crossed bottom is carried out with relatively simple tools. A particularly important aspect of this resides in that in the coordination of the folding and grooving tools the application of glue for closing the crossed bottom only takes place after the bottom closing tools have already substantially effected their operation, and that therefore they can no longer come in contact with the glue or the applied glue layer. If these conditions are ice met, then the result is obtained that due to the simple tools that are used and to the exclusion of the danger of soiling these tools, the particular cross-bottom bag machine can operate at particularly high speed, i.e., the high efiiciency of the machine that is desired may be attained. The cross-bottom bag selected for the particular manufacturing method must, on the other hand, be such that the requirement in accordance with the invention of obtaining a powder-proof or sealed bag is simultaneously accomplished.

Accordingly the invention begins with a method for manufacturing preferably multilayer cross-bottom bags of paper, plastic or the like, and this method is intended to produce such a cross-bottom bag where each triangular bottom pocket has an outer bottom pocket triangle, the hypotuenuse of which is formed by the connecting line of the associated end points of the folding lines of the bottom flaps. To this hypotenuse a further triangle is to be connected by means of the corner flaps formed by incisions. This additional triangle with the corner flaps is connected with the bottom flaps disposed below them. Such a cross-bottom bag is known, for example, from German patent application N 8246 VII/54b published on Sept. 6, 1956. The application papers of this application show that the cross-bottom is turned over in the conventional manner at the ends of the tubular blank that is fed in transversely. After grooving the folding lines for the bottom flaps, the application of glue takes place for the longitudinal gluing of the bottom flaps as well as also for the closure at the triangular bottom pockets, and now the cross-bottom must be closed, which takes place in a manner that in sequence the bottom flaps are brought into closing position but that simultaneously also the turning over of the triangular flaps takes place. It is apparent that for these simultaneous folding operations for the bottom flaps and for the triangular flaps very complicated tools are required, and since before the execution of these folding operations the glue application has already taken place, there still exists also the direct danger that these folding tools are soiled during their operation by the application of glue that took place before. Owing to these conditions the cross-bottom bag machine used for carrying out this method is not capable of operating with high efficiency and to produce a powder sealed bag with little waste.

As compared to this, the method in accordance with the invention resides in that first the folding of the crossbottom takes place in the conventional manner and that subsequently, again in a known manner, the folding lines of the bottom flaps are grooved.

Contrary to the previous state of the art for producing these specially selected cross-bottom bags, the production of these cross-bottom bags is effected in accordance with the invention in such a manner that subsequently the bottom flaps and the aforementioned folding lines are folded, but that in this connection the outer flaps are folded outwardly about the hypotenuse of the outer bottom pocket triangles.

Now the decisive feature for the method in accordance with the invention is that only at this stage of operation in producing cross-bottom closures the necessary application of glue takes place. First the gluing of the bottom flaps is effected. This takes place in a manner that after the gluing of both bottom flaps, the top bottom flap is slightly raised so that the application of the glue takes place by means of a glue wheel or a glue nozzle between manner of producing the cross-bottom closure in accordance with the invention permits of glue application in strokes for the longitudinal gluing of the bottom flaps and of the triangular corner flaps by means of glue nozzles. If in this connection a high-grade glue of artificial resin or a hot glue is employed, then the drying periods for the effected glue applications are essentially shortened, which is also an aspect that greatly favors the high machine efliciency to be attained.

In accordance with the invention the individual successive working operations in the production of the crossbottom bag explained hereinabove are so distributed that for each step of operation simply constructed rotating individual tools known per se are used, one after the other. This means that a machine can be obtained that operates without interruption which works with a correspondingly high number of rotations. During these grooving and folding operations the cross-bottom bag is not yet provided with the glue application. These tools therefore cannot be soiled with glue. Merely during the last operating step, i.e., the turning over of the outer or corner flaps onto the bottom flaps that are already in closing position, the application of glue for these outer or corner flaps takes place as before. Since, however, these corner flaps must be applied from the outwardly directed flat position only through an angle of 180 onto the bottom flaps, the tools required for this can no longer come in contact with the glue deposit on these corner flaps which later are disposed inwardly.

With this method the glue application in the final closing phase of the manufacture of the cross-bottom closure can take place in strips. An application in particular form, for example triangular shape, which is a compulsory requirement in connection with many other cross-bottom closures, is not necessary. The application in strips, on the other hand, is the requisite for the glue application taking place by means of glue nozzles. Such an application in strips or lines not only can be effected more rapidly, but it permits the application of an accurately dosed quantity of glue. Consequently, saving of glue is effected, and the glue which is applied in strips or lines and in a very thin layer insures moreover a particularly tightly glued bottom closure.

Brief description of the drawings Further advantages and details for carrying out the method in accordance with the invention will become apparent from the following description with reference to the embodiment illustrated in the accompanying drawings, and in which:

FIG. 1 shows a tubular blank with the grooved or folding lines indicated in dot and dash lines;

FIG. 2 shows the tubular blank after the two crossed bottoms have been folded;

FIG. 3 shows the crossed bottom bag where, as compared to FIG. 2, the bottom flaps are already in closing position while the triangular flaps are still directed outwardly;

FIG. 4 is a section taken along line IV-IV in FIG. 3;

FIG. 5 shows a bottom triangle with the triangle flap directed outwardly as in FIG. 3 but with the glue applied and to a larger scale;

FIG. 6 shows an end of the crossed bottom bag with the completed closed crossed bottom.

Description of the invention The tubular blank 1 is fed into the crossed bottom machines sideways or in transverse position by means of machines accessories or components known per se. The fold lines 2 and 3 for the subsequent bottom folds and the fold lines 4, 4a, 5, 5a for forming the triangular bottom pockets are formed by means of grooving wheels.

In the next operating station of the cross-bottom bag machine the crossed bottoms 6 and 7, and 6a and 7a, are drawn up and folded. This is done in a manner known per se by means of known folding devices. In FIG. 2 the fold lines 2a, 2b and 3a, 3b are indicated. The grooved lines 4, 4a and 5, 5a register with the edges of the small sides (cathedi) of the triangles 8, 8a, 9, 9a of the triangular pockets 10, 10a and 11, 11a formed as in FIG. 2.

The incisions 12, 12a and 13, 1301, Which as seen in FIG. 1 were already made in the tubular blank as this blank was made, are located in the folded cross-bottom in the associated triangular bottom pockets 10, 10a and 11a. The triangular bottom pocket 11 has no incisions because here the opportunity to introduce a filling tube or valve is to be preserved.

The dot and dash lines 14, 14a and 15 indicate the hypotenuses for the outer triangular pockets 16, 16a, 17a. The bottom flaps 18, 18a which are produced by said incisions are eventually folded about there hypotenuse lines 14, 14a and 15.

In the next operating station bottom flaps 19, 19a are folded inwardly about the grooved lines 2b, 2a, so that the bottom flap 19a (see FIG. 3) is located below bottom flap 19. At this stage the corner or closure flaps 18, 18a are now directed outwardly as seen in FIG. 3.

Only after the bottom closure is prepared in this manner the application of glue begins. For this purpose, as indicated by the section in accordance with FIG. 4, the bottom flap 19 is raised somewhat, so that the application of glue 20 can be made onto the flap 19a which is disposed below it.

After this glue application 20 for the longitudinal gluing of the bottom closure 19, Ha, there is now a broad spread of glue 21 applied to the corner flap 18a of the bottom triangle, and after this glue application has also been effected the corner flaps 18, 18a of the bottom triangles are turned over about the folding lines 14, 14a, and this results in the finished closed cross-bottom as illustrated in FIG. 6.

It should be noted that the method in accordance with the invention is also applicable when the incisions 12, 12a and 13 are not applied to this crossed bottom-closure. In that event it is advisable that already when the tubular section is cut off, small triangular cuts are severed at the three corners where no filling or pouring tabulations are provided. Also in this case a tight bottom closure is obtainable as well as high output of the cross-bottom bag machine. A

Having now described my invention with reference to the embodiment illustrated in the drawings, I do not wish to be limited thereto, but what I desire to protect by Letters Patent of the United States is set forth in the appended claims.

I claim:

1. Method for the manufacture on a cross-bottom bag machine of cross-bottom bags of paper, plastic or the like, where each triangular bottom pocke't has an outer bottom pocket triangle whose hypotenuse is defined by the connecting line between the associated end points of the folding lines of the bottom flaps and Where a further triangle having corner flaps formed by incisions extends from this hypotenuse, which corner flaps are joined to the underlying bottom flaps, said method comprising the steps of providing a tubular blank with incisions to define the corner flaps on the further triangle, forming the crossbottom in a conventional manner, subsequently grooving the folding lines for the bottom flaps in a manner known per se, folding the bottom flaps along the folding lines while turning over outwardly the inner border of the bottom pockets carrying the corner flaps together with the corner flaps about the hypotenuse of the outer bottom pocket triangles and only then applying glue first to one of the bottom flaps and gluing said bottom flaps, and then applying glue to the corner flaps and gluing them onto the bottom flaps.

2. Method in accordance with claim 1, where the application of glue for the longitudinal gluing of the 5 bottom flaps is in strips and for the flaps of the triangles 2,955,517 the glue is spread on. 3,043,199 3,253,389 References Cited UNITED STATES PATENTS 5 639,087 3,195,424 7/1965 Camerini 9335 959 514 3,366,018 1/1968 Civitello 93-35 3,397,622 8/1968 Goodwin 9335 3,413,898 12/1968 Calvert 9335 10 318,016 5/1885 Onderdonk 93-35 2,609,734 9/1952 Bardet 93-8 9336, 58

10/ 1960 Honsel 938 7/1962 Niemeyer 938 5/1966 Miller 9356 FOREIGN PATENTS 6/1928 France. 3/1957 Germany.

WAYNE A. MORSE, 111., Primary Examiner US. Cl. X.R. 

